Traffic signal



E. F. WATER BOR Oct. 5, 1937.

ATRAFFIC SIGNAL Filed June 29, 1936 7gg/1155559551@ fv FIGA.

[N VNTOR ELMER F. WATERBOR B Y I LWun/U uw. .J3 uw.

` A TTORN Ys Patented Oct. 5, 1937 UNITED STATES PATENT OFFICEY Michigan Malleable Iron Company, Detroit,

Mich., a corporation of Michigan Application June 29,

7 Claims.

The invention relates to traic signals of that type in which a signal flag normally extends in upright position in the roadway, but is depressible by the wheels of vehicles passing thereover. It is the object of the invention to obtain a substantial construction which will withstand the use and abuses to which it is subjected, which is easily depressed by the Vehicle wheels without injury thereto, and which will remain in operative condition for an indefinite period of time. With these objects in view, the invention consists in the construction as hereinafter set forth.

In the drawing: Y

Figure 1 is a section of a portion of the pavement showing my improved traiiic signal positioned therein; Y

Figure 2 is an enlarged view of the operating mechanism;

Figure 3 is a transverse section;

Figure 4 is a plan View.

My improved signal comprises a normally upright plate or flag A, preferably having applied thereto the word Stop in plainly visible letters, as indicated at B. Also, if desired there may be arranged on a portion of the surface a reflector unit C which will be illuminated by the headlights of an approaching car. This plate A is mounted on a bed plate D which is embedded in the pavement to be substantially flush with the upper surface thereof and is firmly anchored thereto by suitable means, such as the bolts E at the corners. Extending transversely of this plate isgthe upwardly extending rounded housing F to which the plate A is attached by trunnions G. These trunnions are preferably formed by a shaft extending completely through the housing and out from the opposite endsthereof, being attached to downwardly extending arms A' on the plate A. Centrally beneath the bed plate D and housing F is a downwardly extending cylindrical housing H containing a slidable plunger I resiliently pressed upward by a spring J which seats on the bottom of the housing H. The upper end of the plunger I engages a cam K mounted on the shaft G, which cam is so fashioned that the resilient pressurewill turn it to a position where the plate A extends vertically upward. Thus whenever the plate A is p-ressed downward by the passage of a vehicle wheel thereover, the resilient pressure ofV ficient'to carry the plate beyond this position,

1936, serial No. 88,002

Thus the plate depressed by the forward wheel of a vehicle'might assume a position where its outer edge would strike the following rear wheel to the injury ofthe latter. It is, therefore, an important feature of my improvement that the fiag or plate in returning is prevented from passing beyond its upright position, this being accomplished by the following construction.

L is a.V piston at the lower end of the plunger I which fairly closely fits the cylinder H. Within the skirt of this piston L is the spring J and Y within this'spring a tubular coremember M depending from the upper head' of the piston. This core member has at its lower end a seat N for a ball valve O which may be yieldably pressed to-` wards the seat Vby a relatively light spring P. The chamber within the hollowcoreMis connected by a central port Q and laterally extending ports Q' with a space in the cylinder above the piston. Thus if the cylinder'I-I is filled with liquid, this will not interfere with the free downward movement of the plunger, as thevalve O will be lifted from its seat and the fluid will flow through the hollow core member M and ports Q and Q to the chamber above the piston. VOn the other hand, when the plunger movesV upward the ball O will seat preventing return of fluid through the same channel. However, the fluid is permitted to slowly return through a restricted port R passing through the head of the piston into the annular space in which the spring J is located. Thus in operation the signal or iiag A can be quickly depressed by the wheel passing over it, but its return is suiliciently retarded to limit the kinetic energy or inertial factor, so thatthe cam K will' the best fluid for controlling the plunger or dashl pot. I, therefore, preferablyarrange va head S between the piston L and the upper end of the plunger I, this head being apertured for` the passage of a plunger shank I therethrough. The compartment above the head S is in communication with the chamber within the housing F through ports T through the head woi the plunger so that any lubricating fluid in the housing F is free to pass through these ports intov the chamber above the head S. 'This will permit of using a different uid within the housing F and upper portion of the cylinder H from that whichrisin the lower or dashpot portion ofthe cylinder and consequently the trunnions will be maintained Well lubricated.

, Y pressed position. rThese ramp portionsA U'serve In order to fprovide sucient strength; in the flag plate A to withstand the shocks it is ofY a substantial thickness vand is further provided with a still thicker bead A2 surrounding the central panel. Thus when the plate is flattened down upon the bed plate D, it will be extended upward ktherefrom equal to the thickness ofY the Vbead. A2 and might form anfabrupt shoulder againstwhich the wheel o'f'the vehicle would strike. To avoid such'effect,.I havefprovided on opposite ends of the bed plate D transversely exj tending ramp portionsv U which on their outer sides slope upward from the level of thepavement and on their inner sides form an abrupt shoulder adjacent to the plate -Awhenin deto liftthe wheel passing thereover so as to lessen vthe height that it must be'subseq'uently raisedV to pass over the housing F. The space between the Vramp and the housing is of such small dimension that the wheel'will Ynot materially drop f bearing' against saidpiston. The head S i's apertured-for the insertionof the Vshank VIr'V therethroughand said head'lias a Vshouldered engagemen'tS 'with' 'thel cylinder Hf to preventVv upward af detachable'hea-d or plug V" preferably having a. tapered threaded engagement with saidcylinder and provided ywith a detachable smaller plug e VY through whichv ii'uid can bev introduced.' Thus al1 of the'parts maybe introducedA througnthe v 'Alowerend of vthe cylinderwhen the plug V is refmoved 0and when said plug i's` placed in position these parts will be held from disengagement. n f What I claim as my invention'isf Y 1. VA Y,traiiic `signal comprising a` bed `plate, a signal plate lpivotally mounted Yon said bed plate 4 and rockabl `from a'perpendicular position to a position parallel and adjacentto said bed plate,

d resilient means forfreturni'ng said signal plate to Y 50 its'uprig'htV position after the depression of the vsame-and means for positivelyretarding the speed of return and thereby preventing the swinging of said plate beyond the upright `position during said return movement. 'l

2. VA traftic signal comprising a bed plate, a signal plate pivotally-mounted on said bed plate Y and .rockable from a perpendicular position to a position parallel and adjacentto said'bed'plate,

i* va.;`s'p`ring pressed plunger and coolgerating cam 60' for returning said signal plate 'to uprightY posil' j tion, and adashpot'controlling the return move- 'position parallel and-adjacent to said Ybeu piate,

Imntgpreventinggthe *swingingV of the plate loec yond theupright position@v V31A; traiiio signalvc'omprisingia bed plate, a

signal plate pivotally-mo'unte'd on saidibefd plate and vrockable-froma perpendicular Vposition to' a a housing beneath said bedplate,a springf pressed 'plunger within's'aid housinga caniV connected-to saidl YsignalY-plateV engaging' said; plunger beingY Y -,adapted to depress'the same Vwhen ysaid plate is ffrcfked'downward and funetionigtoreturn the yplatelby the'upward pressure o f said plunger, and la-daslrip'ot within said housingnfor.retarding" the upward movement of said plunger so as t prevent the swinging of said plate beyond its upright position.V

Y 4. Atraiiicsignal comprising a bed plate, a signalplate pivotally mounted on said bed Vplate and rockable from a perpendicular position to a position parallel and adjacent to said bed plate, a housing beneathsaid bedfplate, a'spring-pressed y plunger Within said housing, a cam connected to said signal plate engaging said plunger being #adapted to depress the same when said plate is rocked downward and functioning to return the plate by the upward pressure of .said plunger, a fluid operated dashpot within said housing for retardingfthe upward movement of said plunger'Y so as to prevent the swinging of the plate beyond its upright position, and a partition. separatingY the fluid in saidvdashpot from the Yspace in the upperportion of said housing whereby lubricating Y iiuid for said cam and plunger may be retainedVV in "said housing separate from thefiuid o f said dashpot. Y, Y Y.

5; A traicsignal comprising a bed plate having a central Yupwardly extending vhollow housing integral therewith, la signal plate normally extending perpendicular to said bed plate Vand bifurcated to embrace said hollow housing, a

shaft extending from the furcations of said sig.- n

nal through said hollow housingv to.Y form a pivot permitting rocking of said-,signal platejjfrom a sovr perpendicular position tocar position parallel and Y adjacent to said bed platera camrmountedfon said shaft centrally` thereof, cylindrical housinglbeneath said bed plate and communicating with said hollow housing, a'plunger in'jsaid cy.-

lindrical housing having its upper fend bearing 4against said cam'its lower portion'consti'tuting afpiston movable in said cylindricaljhousing; ,a spring for pressing said'1 plunger upward, lacheck. valve permitting the free passage of fluid from beneath saidv piston tothe space aboveV the same Y but preventing return-movement of said yfluid-,a

restricted passage permitting a slow return o f iiuid from above the piston to the space beneath the same, and an apertured head throughwhich said` plunger passes separating the spaoe'above the piston from the spaceV higher up in y,said Y cylinder whereby lubricating fluid maybe held I in said upper space and within said hollow hous- Ying, said yplunger having passages therethrough Y permitting movement of saidV lubricating fluid' past the same during the reciprocationfof the Yplunger.l Y t Y Y Y Y 6.A traffic signal comprising a bed plate, a

signal plate' pivotally mounted on saifdbed plate and rockable from a perpendicular position to a iorreturning saidrsignal plate to qupright/position, and a ramp on saidbed plate'clearing said signalplatein depressed position and adaptedy to Vraise a-vehicle wheel to the levelithereof. ,Y 7. A traflic signal comprising abed plate, a,

signal plate pivotally mounted onsaid bed plate Y and rockable from a perpendicular position to a position parallel and adjacent to saidV bed plate,

Yposition parallel and adjacentto' said bed plate, "i

a spring pressed plunger and cooperating camVY resilient means for returning* said signal plate Y toY its :upright position after depression of the same, and Vmeans `for positively retarding the speed Yof the return of saidV signal; Plate torits upright position thereby limitingthemomentum j Y thereof Yto be insuilicient to `carry b eyndfsmd 5r f 'upright position 

